Hot-air furnace.



".P'TENTED FEB. 24, 19,03.v

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` HOT AIR Hmmm. APPLICATION FILED MAY 20, 1902.

H0 MODEL.

UNITED STATES" 'PATENT OFFICE.

ROBERT SCHLUMBERGER,OF ALLEGHENY, PENNSYLVANIA.

HOT-AIRAFURNACE.

SPECIFICATION forming part of Letters Patent No. 721,471, dated February 24, 1903. Application tied May 20,1902. saturo. 108.212. A(nomas.)

-a citizen of the United Statesof America, re-

siding at Allegheny, in the county of Allegheny and State of Pennsylvania, have invented certain new and useful Improvements inHot-Air Furnaces, of Which'the following is a specification, reference being had therein to the accompanying drawing. Y

This invention relates to certain new and useful improvements in hot-air furnaces, and is particularly adapted for use in connection with gas as a fuel for producing the heated air.

The invention has forits object to construct a furnace of this character which may be used not only for the heating of buildings as an entirety, but also conveniently used for the heating of single rooms, hallways,sand the like; and another object of the invention istoV so construct the furnace that a greater heating efficiency may be c reatedwithin a neat and compact structure than has heretofore been possible.

A further object of the invention is to provide means for passing the air to be heated directly through the heater, whereby the same will be rapidly heated, and also to provide means for admitting air to the space aroundthe heater and heat this air by the heat thrown off by the heater, so as to increase the effi-V ciency of the device.

Still further objects of the invention are to is supported on an annulus having suitableA supporting-legs, the annulus and legs forming the supporting-stand for the furnace. An inner shell or casing is also supported on the ring or annulus, and the latter is provided between the inner and outer shells or casings with openings forming air-passages, through which cold air enters into the space between the two casings and is heated therein, commingling with the heated air discharged from the interior of the inner casing. A heater of especial construction is arranged within the inner casings and embodies a series of heating-chambers disposed one above the other and soarranged that the casing of each chamber is subjected to the direct action of the flames from the burner upon the shell or casforming a part of this specification and wherein like numerals of reference will be employed to designate like parts throughout the drawing, which shows a central vertical section of my improved heater, the annulus or ring being in perspective and partly broken (away, with the casings of the heating-chambers also in perspective.Y

'To put my invention into practice, I provide a casin g or shell l, preferably made cylindrical in form, thoughvnot necessarily so, this shell 'or casing being provided with a top 2, which in the'present illustration is shown substantially conical in form, andthis top 2 has one or more hot-air outlets 3. 1 is mounted on the supporting-stand, lcomprising an annulus 4, having the upwardly-extending iange 5 around its outer edge and provided adjacent to said flange with a series of cold-air inlets 6,arrangeddcircumferentially in the annulus or ring, so that the cold air may freely enter the casing'l entirelyaround the same at its lower end. This 'annulus or ring 4 is mounted upon suitable supportinglegs 7, which have braces 8, crossing at right angles, as shown, and forming a support for the base of the burner 9, with which the supply-line 10 is connected. The burneris suit Means is,

The shell or casing ICO of considerable capacity will be formed be.

tween the two casings. The inner shell or casing has an inwardly-extending flange 14 at its lower end, which is provided near its outer edge with circumferentially-arranged openings 15. Mounted within this shell or casing 11 is the heater, which consists of a series of heating pans or shells each having a heatingchamber and disposed one above the other. In the present illustration I have shown three of these shells or pans, which is sufficient to illustrate the principle of the invention, though two, three, or more may be employed. These heating shells or pans are each of the same general shape, being somewhat in the form of a frustrated cone, and they are disposed within the shell or casing 11 one above the other, as shown. The lower shell or heating-pan 16 and the upper shell or heating-pan 2O are substantially of the same size and are considerably less at their `greatest diameter than the diameter of the central heating shell or pan 18, interposed between the pans or shells 16 20. The central heating shell or pan 2O is of a diameter equal to the interior diameter of the shell or casing 11, so as toform a neat tit with the inner wall of said casing 11 for a purpose as will presently appear. The lowermost shell or pan 16 carries air-inlet tubes 17, which extend through the openings 15 in the flanges 14 and project a considerable distance below the said flange 14, the lower ends of these air-tubes being below the discharge end of the burner 9, so that the llames from the burner will not be drawn into the tubes. The base of the pan 16 is, however, somedistance above the flange 14 in order that when the llames strike the bot-- tom of said pan or shell16 they will be dellected and spread entirely around the pan. The central pan or shell 18, as stated, is of a diameter to fill the interior of the casing 11, and this central pan is provided with a central llue 24, establishing communication between the space above the pan 18 and the space below the said pan or shell. This central pan or shell 18 also carries air-tubes 19, establishing communication between the chamber in said pan or shell and the chamber in the pan or shell 16. The uppermost pan or shell 20 carries air-tubes 2l, establishing communication between the chamber orspace in said shell or pan and the chamber or space in the pan or shell 18, and the chamber or space in the pan 2O is in communication with the hot-air space 22 within the top of the outer casing 1 by a central hot-air flue 23. I preferably construct these pans or shells in which the air is heated each with the depending air-tubes and construct the central pan or shell and the lowermost one with openings in the top plate to receive the depending tubes. The top plate of the uppermost shell or pan is provided with the opening to receive the hot-air tube 23.

An exit ilue or chimney extends through the outer casing 1 and communicates with the interior of the casing 11 at a suitable point with the chamber 26 and carries off the products of combustion.

By reason of the draft being shut oil along the inner wall ofthe casing 11 by the top plate of the heating shell or pan 18 contacting with said wall the draft from the exit-flue 25 will be between the top heating shell or pan 2O and the central heating pan or shell 18 through the central ilue of said shell or pan, the flame being drawn in between the central pan or shell 18 and the lowermost pan or shell 16, as shown. This diverting ot' a direct natural draft up the inner wall ot` the casing 11 to the exit-flue 25 causes all three of the heating shells or pans embodied in the heater to be subjected to the direct action of the flames, and thereby be subjected to much greater heat than would otherwise be the case, causingthe same to become heated to a much greater extent and largely increasing the heating ability of the device. Owing to the fact that the pans or shells become highly heated, owing to the fact that they are subjected to the direct action of the llames, the shell 11 will consequently throw oft considerable heat, which will heat the air that passes into the space 12 through the air-inlets 6, this heated air :rising within the space 12 to the space 22 at the top of the outer casing and being discharged with the heated air which is delivered into said space 22 through the hotair fine 23. I also desire to call attention to the fact that the air-tubes 17 1!) 21 are disposed so as not to be in line with each other, and the air is thus caused to travel more IOO IIO

slowly through the successive pans or heating-chambers, so that the same will be heated to a greater extent before it is discharged .into the chamber 22 and from thence through above the other with the bottom of each vpan` in communication with the bottom of the adjacent pan or shell, substantially as described.

2. In a lhot-air furnace, a supporting annulus or ring provided with cold-air inlets, an outer shell or casing supported on said ring and provided at its upper end with hot-air outlets, an inner shell or casing supported on the annulus, a heater comprising a series of heating chambers disposed one above the other and in communication the one with the other, a burner arranged beneath the lowermost chamber, and a hot-air Hue establishing communication between the upper chamber of the heater and the hot-air space within the outer shell or casing, substantially as described.

3. In a hot-air furnace, an outer shell or casing provided with hot-air outlets, an inner shell communicating at its upper end with a space at the top of the outer shell, a supportingstand having an annulus on which the outer and inner casings rest, said annulus having openings to admit air to the space between the casings, an exit-flue communieating with the inner shell or casing, and a heater comprising a series of heating-cham bers disposed one above the other and in communication with each other, the shell or casing of one of the said chambers engaging the inner wall of the inner casing, as and for the purpose described.

4. In a hot-air furnace, the combination with an outer shell or casing having hot-air outlets at its top, an inner shell or casing,

' with an inner and outer casing, and a common support for said.v casings, said support provided with circumferentiallyarranged openings to admit air to the space between the casings, of a heater comprising a series of heating shells or pans disposed one above the other, the chambers of said shells or pans in communication, one of said shells or pans being of greater diameter than the others and engaging the inner wall ofthe inner casing,

and a burner supported beneath the lower most heating shell or pan, substantially as described.

In testimony whereof I affix my signature in the presence of two witnesses.

ROBERT SCHLUMBERGER.

Witnesses:

JOHN NOLAND, E. E. POTTER. 

